package controller;

import org.apache.commons.fileupload.FileItem;
import org.apache.commons.fileupload.FileUploadException;
import org.apache.commons.fileupload.disk.DiskFileItemFactory;
import org.apache.commons.fileupload.servlet.ServletFileUpload;
import sun.misc.BASE64Decoder;

import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.awt.image.BufferedImage;
import java.io.*;
import java.util.Iterator;
import java.util.List;
import java.util.UUID;

@WebServlet( "/UserController ")
public class UserController  extends HttpServlet {
    private static final long serialVersionUID = 1L;
    @Override
    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request, response);
    }
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //判断上传表单是否为multipart/form-data类型
        if(ServletFileUpload.isMultipartContent(request))
        {

            try {
                //1. 创建DiskFileItemFactory对象，设置缓冲区大小和临时文件目录
                DiskFileItemFactory factory = new DiskFileItemFactory();


                //2. 创建ServletFileUpload对象，并设置上传文件的大小限制。
                ServletFileUpload  sfu = new ServletFileUpload(factory);
                sfu.setSizeMax(10*1024*1024);
                //以byte为单位    不能超过10M  1024byte = 1kb  1024kb=1M 1024M = 1G
                sfu.setHeaderEncoding("utf-8");

                //3. 调用ServletFileUpload.parseRequest方法解析request对象，得到一个保存了所有上传内容的List对象。
                List<FileItem> fileItemList = sfu.parseRequest(request);
                Iterator<FileItem> fileItems = fileItemList.iterator();

                //4. 遍历list，每迭代一个FileItem对象，调用其isFormField方法判断是否是上传文件
                while(fileItems.hasNext())
                {
                    FileItem fileItem = fileItems.next();
                    //普通表单元素
                    if(fileItem.isFormField())
                    {
                        String name = fileItem.getFieldName();//获取文件名
                        String value = fileItem.getString("utf-8");//设置字符集
                    }
                    //<input type="file">的上传文件的元素
                    else
                    {
                        String fileName = fileItem.getName();//文件名称
                        System.out.println("原文件名：" + fileName);

                        //a.随机生成一个唯一标记
                        String id = UUID.randomUUID().toString();
                        //与文件名拼接
                        fileName = id + fileName;

                        String realPath=getServletContext().getRealPath("/WEB-INF/upload");

                        //5. 调用FileItem的write()方法，写入文件
                        File file = new File(realPath,fileName);
                        System.out.println(file.getAbsolutePath());
                        fileItem.write(file);

                        //6. 调用FileItem的delete()方法，删除临时文件
                        fileItem.delete();
                        /*
                         * 存储到数据库时注意
                         *     1.保存源文件名称   Koala.jpg
                         *  2.保存相对路径      image/1478509873038.jpg
                         *
                         */
                        System.out.println(fileName);
                        request.setAttribute("image_name",fileName);
                        request.setAttribute("image_path","upload/"+fileName);
                        request.getRequestDispatcher("./index.jsp").forward(request, response);
                    }
                }

            } catch (FileUploadException e) {
                e.printStackTrace();
            } catch (Exception e) {
                e.printStackTrace();
            }


        }
        }
       /* String path=getServletContext().getRealPath("/");
        String filePath="upload/";

        String msg="default";

        //      base64 图片
        String base64Img=request.getParameter("icon");
        BASE64Decoder decoder=new BASE64Decoder();
        if(base64Img!=null&&!"".equals(base64Img)){
            try {
                byte[] b=decoder.decodeBuffer(base64Img);
                String name=System.currentTimeMillis()+".jpg";
                filePath+=name;
                File file=new File(path+filePath);
                ByteArrayInputStream is=new ByteArrayInputStream(b);
                BufferedImage bi= ImageIO.read(is);
                ImageIO.write(bi, "jpg", file);
                is.close();
                msg="上传成功";
                System.out.println("上传成功！");
            } catch (Exception e) {
                e.printStackTrace();
                msg="上传失败";
                System.err.print("上传失败");
            }
        }else{
            msg="上传失败";
            System.err.print("上传失败");
        }
        response.getWriter().println("{\"msg\":\""+msg+"\",\"imagePath\":\""+filePath+"\"}");*/
}
